Rainfall-induced Landslide Hazard Analysis Based on GIS in Yanbian Region, China

Liu,Xiu Xuan,Quan, He Chun,이병걸 대한공간정보학회 2017 대한공간정보학회지 Vol.25 No.4

This paper mainly studies landslide hazard in Yanbian region,8 landslide factors of soil moisture content, hydrogeology, land use type, slope, slope aspect, fault, river and rainfall are analyzed in the area of Yanbian region. Using the analytic hierarchy process (AHP), the relative weights of 8 landslide factors were obtained, and the internal weights of each factor were determined by the data; the rainfall factors were then divided into three categories such as average annual rainfall, average flood season rainfall, and the maximum average rainfall. And the comparison of the rainfall factors was made. Finally based on the results of these weights to the remote sensing technology(RS) and geographic information system(GIS) technology combined to evaluate its area, we are mapping the risk assessment area for landslide hazard in Yanbian region. According to the map analysis, figure in the dangerous hierarchies result in accordance with the historical landslides is better. At the same time. landslides and hazard area of statistical data analysis showed that the AHP method combined with GIS technology is suitable for promoting the Yanbian regional landslide hazard assessment.

권협(權悏) 고급사(告急使)의 연행(燕行)에 대하여

劉寶全(Liu Bao?quan) 가천대학교 아시아문화연구소 2008 아시아문화연구 Vol.14 No.-

During the period of Chosun Dynasty, the works named Record of Trip in Yan(燕) by some envoy from Korea to China provided a large number of attractive and rare historical data to future generations. It’s also a complement to something not concerned in official history. These travel notes are important information on researching the history of relation between China and Korea. In the Record of Trip in Yan of Seoktanggong(石塘公), which was written in the style of diary, Kuang Hyeop(權?) recorded the process of his trip in Ming Dynasty as a envoy before the year of 1597 when the War against Japanese Troops happened. The thesis takes the record as basic information, and analyzes the event of requesting rescue when Kuang Hyeop was in Beijing. He went in for purchasing military supplies and the process of determining whether the Ming Dynasty would rescue Chosun. The diplomatic mission of Kuang Hyeop was an important part of the relation between China and Korea during the period of Imjin Waeran. Also, his Record of Trip in Yan provided strong evidence for researching the relation between the two countries.

One simple, rapid and economical method for ploidy detection of Trichogramma dendrolimi Matsumura (Hymenoptera Trichogrammatidae)

Liu Quan-quan,Zhang Chen,Zhou Jin-cheng,Dong Qian-jin,Huo Liang-xiao,Dong Hui 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.2

Ploidy diversity provides valuable scientific information, thus making the detection technique of ploidy important. However, traditional methods of cytological observation and flow cytometry are either laborious or expensive. We here report a simple and rapid, effective and economical quantitative PCR (qPCR) approach to determine the ploidy of a parasitoid species Trichogramma dendrolimi Matsumura, an economically important biocontrol agent. We applied a mitochondrial gene cytochrome oxidase (COI) and a nuclear gene forkhead to evaluate the mitochondrial number per nuclear copy in a thelytokous Wolbachia-infected strain of T. dendrolimi and its bisexual uninfected counterparts. The 2 −ΔCq values calculated from C q values which resulted from qPCR experiments were significantly larger in haploid males than that in diploid females. Haploid males possessed about 2.69 times mitochondrial number per nuclear copy as diploid females. Not a single significant difference was found between diploid females from thelytokous and bisexual strains. Based on the differences in relative mitochondrial content, we were allowed to distinguish between haploid males and diploid females. Moreover, the number of mitochondria significantly decreased with higher ploidy level but was not affected by Wolbachiainfection. Our study supplied an available tool to investigate the ploidy diversity in sex determination of T. dendrolimi and thelytokous manipulation of Wolbachia, which is the crucial step to further study their underlying mechanisms. This will in turn contribute to the biocontrol efficiency by enhancing the female production and hence the parasitism rate.

Nanotwinned Microstructure Engineering of Electroplated Copper for Enhanced Anti-corrosion in Alkaline Medium

Xing‑Quan Liu,Zhe Li,Zhen‑Jia Peng,Rui‑Xun Wang,Zhi‑Quan Liu 대한금속·재료학회 2024 METALS AND MATERIALS International Vol.30 No.1

Electroplated copper is a key electronic interconnect material in integrated circuits and printed circuits and inevitablyexposed to corrosive media in manufacturing processes. The present work reports, for the first time, that corrosion resistanceof electroplated copper in 4 wt% NaOH is enhanced via nanotwinned microstructure engineering. Nucleation and growthof oxide/hydroxide on nanotwinned copper are inhibited, attributed to existence of highly (111)-preferred grain orientationand high-density parallelly-aligned coherent twin boundaries at surface. This study unveils a novel anti-corrosion strategyof nantowinned microstructure engineering against alkaline etchant, and exhibits great application values in industrial electroplatingof copper, silver, or their alloys.

Attack-Proof Cooperative Spectrum Sensing Based on Consensus Algorithm in Cognitive Radio Networks

( Quan Liu ),( Jun Gao ),( Yunwei Guo ),( Siyang Liu ) 한국인터넷정보학회 2010 KSII Transactions on Internet and Information Syst Vol.4 No.6

Cooperative spectrum sensing (CSS) is an effective technology for alleviating the unreliability of local spectrum sensing due to fading/shadowing effects. Unlike most existing solutions, this paper considers the use of CSS technology in decentralized networks where a fusion center is not available. In such a decentralized network, some attackers may sneak into the ranks of cooperative users. On the basis of recent advances in bio-inspired consensus algorithms, an attack-proof, decentralized CSS scheme is proposed in which all secondary users can maintain cooperative sensing by exchanging information locally instead of requiring centralized control or data fusion. Users no longer need any prior knowledge of the network. To counter three potential categories of spectrum sensing data falsification (SSDF) attacks, some anti-attack strategies are applied to the iterative process of information exchange. This enables most authentic users to exclude potentially malicious users from their neighborhood. As represented by simulation results, the proposed scheme can generally ensure that most authentic users reach a consensus within the given number of iterations, and it also demonstrates much better robustness against different SSDF attacks than several existing schemes.

<i>Nardostachys jatamansi</i> Ethanol Extract Ameliorates Aβ42 Cytotoxicity

Liu, Quan Feng,Jeon, Youngjae,Sung, Yung-wei,Lee, Jang Ho,Jeong, Haemin,Kim, Young-Mi,Yun, Hye Sup,Chin, Young-Won,Jeon, Songhee,Cho, Kyoung Sang,Koo, Byung-Soo Pharmaceutical Society of Japan 2018 BIOLOGICAL & PHARMACEUTICAL BULLETIN Vol.41 No.4

5-Aza-2'-deoxycytidine Induces Hepatoma Cell Apoptosis via Enhancing Methionine Adenosyltransferase 1A Expression and Inducing S-Adenosylmethionine Production

Liu, Wei-Jun,Ren, Jian-Guo,Li, Ting,Yu, Guo-Zheng,Zhang, Jin,Li, Chang-Sheng,Liu, Zhi-Su,Liu, Quan-Yan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

In hepatocellular cancer (HCC), lack of response to chemotherapy and radiation treatment can be caused by a loss of epigenetic modifications of cancer cells. Methionine adenosyltransferase 1A is inactivated in HCC and may be stimulated by an epigenetic change involving promoter hypermethylation. Therefore, drugs releasing epigenetic repression have been proposed to reverse this process. We studied the effect of the demethylating reagent 5-aza-2'-deoxycitidine (5-Aza-CdR) on MAT1A gene expression, DNA methylation and S-adenosylmethionine (SAMe) production in the HCC cell line Huh7. We found that MAT1A mRNA and protein expression were activated in Huh7 cells with the treatment of 5-Aza-CdR; the status of promoter hypermethylation was reversed. At the same time, MAT2A mRNA and protein expression was significantly reduced in Huh7 cells treated with 5-Aza-CdR, while SAMe production was significantly induced. However, 5-Aza-CdR showed no effects on MAT2A methylation. Furthermore, 5-Aza-CdR inhibited the growth of Huh7 cells and induced apoptosis and through down-regulation of Bcl-2, up-regulation of Bax and caspase-3. Our observations suggest that 5-Aza-CdR exerts its anti-tumor effects in Huh7 cells through an epigenetic change involving increased expression of the methionine adenosyltransferase 1A gene and induction of S-adenosylmethionine production.

Studies on the Soybean Cyst Nematode (Heterodera glycines) in China

Liu, Wei-Zhi,Liu, Ye,Duan, Yu-Xi,Hong, Quan-Chun,Wang, Ke-Ning Korean Society of Applied Entomology 1995 한국응용곤충학회지 Vol.34 No.2

Soybean has been cultivated in China for 5,000 years. The soybean cyst neamtode (SCN), Heterodra glycines, was recongnized in Northeastern China in 1899. Currently, it is known to occur in 12 provinces. The biology of SCN was investigated in several provinces. Six races of SCN were identified (race 1, 2, 3, 4, 5 and 7). About f10,000 soybean germplasm lines were evaluated for their resistance to race 1, 3, 4 and 5 of SCN. At least two black-seeded cultivars are resistant to all four races. Several tolerant soybean cultivars with yellow seed coat were released and are in production. Additional resistant cultivars are being developed. Nematicides were not applied in production Potential biocontrol agents and related aspects are being investigated.

Cooperative Control Feedback: On Backoff Misbehavior of CSMA/CA MAC in Channel-Hopping Cognitive Radio Networks

Quan Liu,Yong Lu,Gang Hu,Shaohe Lv,Xiaodong Wang,Xingming Zhou 한국통신학회 2018 Journal of communications and networks Vol.20 No.6

Due to dynamic channel availability in cognitive radionetworks (CRNs), rendezvous problem is known as the mostchallenging issue in the design of media access control (MAC)protocol, which is a key step for secondary users (SUs) to startcommunication. With the concept of blind rendezvous, numerouschannel-hopping sequence (CHS) based rendezvous schemeshave been proposed to solve this problem in these years. Currently,little attention is paid to the design of a carrier sensing multipleaccess/collision avoidance (CSMA/CA) MAC based on theserendezvous schemes and also the rendezvous de-synchronizationproblem brought by multiple rendezvous networking paradigminto MAC design. To this end, we propose a cooperative channelhoppingbased CSMA/CA MAC (named CoCH-CSMA/CA MAC)which works on the top of existing CHS based rendezvous schemes. Resulting from the rendezvous de-synchronization problem, a newtype of collision, named false collision, is identified. As a SU cannotdiscern the false collision by itself, we design a cooperative controlfeedback scheme which employs correlation-based signal detectionto reduce the coordination overhead of cooperation and helps SUsto avoid backoff misbehavior. Moreover, we analyze the behavior ofour MAC protocol and its advantage. Extensive simulations provethat the cooperative control feedback scheme can effectively alleviatethe impact of rendezvous de-synchronization problem on backoffmisbehavior and improve network performance.

Analysis and Optimization of Cooperative Spectrum Sensing with Noisy Decision Transmission

( Quan Liu ),( Jun Gao ),( Yunwei Guo ),( Siyang Liu ) 한국인터넷정보학회 2011 KSII Transactions on Internet and Information Syst Vol.5 No.4

Cooperative spectrum sensing (CSS) with decision fusion is considered as a key technology for tackling the challenges caused by fading/shadowing effects and noise uncertainty in spectrum sensing in cognitive radio. However, most existing solutions assume an error-free decision transmission, which is obviously not the case in realistic scenarios. This paper extends the general decision-fusion-based CSS scheme by considering the fading/shadowing effects and noise corruption in the common control channels. With this more practical model, the fusion centre first estimates the local decisions using a binary minimum error probability detector, and then combines them to get the final result. Theoretical analysis and simulation of this CSS scheme are performed over typical channels, which suggest some performance deterioration compared with the pure case that assumes an error-free decision transmission. Furthermore, the fusion strategy optimization in the proposed cooperation model is also investigated using the Bayesian criteria. The numerical results show that the total error rate of noisy CSS is higher than that of the pure case, and the optimal values of fusion parameter in the counting rule under both cases decrease as the local detection threshold increases.